Pneumatic timing device



y 1966 s. s. TROMBATORE ETAL 3,262,374

PNEUMATIC TIMING DEVICE Filed May 2'7, 1964 FIG. 1

I N VE N TORS Sam 5. Wombaiora Wilbur J Bradtkc W2 ll 1%; J. Griswold,

United States Patent 3,262,374 PNEUMATIC TIMING DEVICE Sam S.Trombatore, Des Plaines, Wilbur J. Bradtke, Park Ridge Manor, andWilliam J. Griswold, Bridgeview, Ill., assignors to Webcor, Inc.,Chicago, 11]., a corporation of Illinois Filed May 27, 1964, Ser. No.370,407 10 Claims. (Cl. 9216) This invention relates to a pneumatictiming device.

One of the objects of this invention'is the provision of a timing deviceincluding a moveable ram which at the end of a predetermined interval isoperttive to per form a desired function.

Another object of this invention is the provision of a pneumatic timingdevice which at the end of a predetermined interval is operable todischarge a burst of pressure fluid for use as a propelling or actuatingforce or for pressurizing purposes.

A further object of this invention is the provision in a pneumatictiming device of means for varying the timing interval.

Still a further object of this invention is the provision of means in apneumatic timing device for selectively rendering the same operative orinoperative.

Still a further object of this invention is the provision of novel meansfor releasably locking a moveable ram against movement.

Other and further objects and advantages of this invention will becomeapparent from the following description when the same is considered inconnection with the accompanying drawings in which,

FIG. Us a side elevational view of a pneumatic timing device inaccordance with our invention;

FIGS. 2 and 3 are left and right hand end elevational viewsrespectively;

FIG. 4 is a cross-sectional view taken substantially on .line 44 of FIG.3;

FIG. 5 is a cross-sectional view taken substantially on line 55 of FIG.3, with the parts in a different operative position and with certainparts rotated and others eliminated for greater clarity.

FIGS. 6 and 7 are views similar to FIG. 5, but showing the parts indifferent stages of operation and with certainof the parts rotated forgreater clarity.

FIG. 8 is a cross-sectional View taken substantially on line 8-8 of FIG.4;

FIG. 9 is a cross-sectional view taken substantially on line 99 of FIG.4;

FIG. 10 is a view similar to FIG. 8 but showing the parts in a differentoperative position.

Referring to the drawings, the numeral indicates a casing or-body havinga cylindrical chamber or bore 16. At the rearward end of the casing 15the bore 16 is reduced in diameter to provide an annular shoulder 17.The reduced diameter portion of the bore is provided with an annulargroove in which is received a resilient O-ring sealing member 18. Thewall of the casing 15 is drilled and tapped at spaced points to affordconnections as at 19 and 21 to conduits connected to a source ofpneumatic pressure fluid. An end member 22 provided with an annularflange 23 is received within the reduced diameter portion of the borewith the flange 23 abutting against the shoulder 17 and with O-ring 18in sealing engagement with the cylindrical surface of end member 22. Endmember 22 is provided with an axial bore 24 and with a counter-boredaperture 26 which is disposed eccentric to the bore 24. A stud 27preferably threaded at bothends is provided with an intermediate flange28 and passes through the counter-bored aperture 26 with the flangereceived in the counter-bore of the aperture An O-ring 29 circumposedabout the stud adjacent the flange affords a seal between the stud 27and the aperture 26. One end of stud 27 extends outwardly of end member22 and is arranged to engage with a lock nut 31 which affords means forrotating the stud, for a purpose as will be hereinafter explained.

An end member 32 provided with a stepped cylindrical surface cooperateswith the opposite end of the casing 15, in the manner illustrated. Saidend'member is secured to the casing 15 by a plurality'ofcircumferentially spaced bolts 33 which pass through apertures in theend member and engage in correspondingly threaded openings in the wallof the casing. End member 32 is provided with an annular recess in whichis received an O-ring 34 affording a fluid tight seal between the endmember and the casing 15. The end member also is provided with an axialbore 36 which is lannularly grooved to receive an O-ring 37.

A ram 38 shaped substantially as illustrated includes a cylindrical mainbody portion 39 and an end portion 41 of reduced diameter providing anannular'shoulder 40. An annular groove 42 is provided in the main bodyportion 39 and a similar groove 43 is provided in the red-uced portion41 to receive an O-ring 44 which affords a liquid tight seal between endmember 22 and the ram at one end, while the O-ring 37 affords acorresponding seal between end member 32 and the ram at the opposite endof the casing. The ram 38 is axially slideable relative to the casing.

A disk-type piston 46 is provided with a central bore to receive the ram38 and is provided with inner and outer annular grooves in which arereceived O-rings 47 and 48 alfording fluid tight seals between thecasing 15 and piston 46 and the ram 38 and the piston. The piston 46 isaxially slideable relative to the ram 38, as will be hereinafterexplained.

Referring to FIG. 4, the piston 46 is provided with a bleed aperture andvalve seat 49 and carries a cooperat-' ing threaded valve stem51 foradjusting the flow of fluid through the aperture. A coiled spring 52circumposed about the ram 38 is interposed between the piston 46 and theend member 22 and normally tends to urge the piston in a directiontowards the left, as viewed in FIG. 4.

As will be apparent by reference to FIG. 4 the ram 38 permanently isrestricted against movement to the right by reason of the annularshoulder 40 abutting against end member 22. In the course of operationof the device of our invention, the ram 38 is restricted againstmovement to the left, as viewed in FIG. 4, by a locking or latchingmeans which comprises a pair of generally cylindrical rod members 53disposed at diametrically opposed points on the ram, with the medialportion of each rod member being machined or cut away substantially to adiametral line as illustrated clearly in FIG. 8. The rod members 53 arereceived in the annular groove 42 with the flat faces of the machinedareas engaging against the bottom of the annular groove. A pair ofcoiled springs 54 are disposed at opposite ends of the rod members andserve to draw the rod members in a direction towards each other so as toinsure seating of each rod member Within the groove. Annular recessesare provided in the ends of the rod members to retain the end loops ofthe springs 53 so as to prevent inadvertent displacement of the same.Anchored in each rod member53 is a pin 56 which is angularly disposed inrelation to the plane of the flat face of the machined portion so thatthe pins 56 assume the angular relationship substantially as illustratedin FIG. 4. It will be understood that the springs 54 afford sufficienttension to maintain the rod members 53 within the annular groove 42 inthe relationship illustrated in FIGS. 4 and 8 and when so disposed therod members afford a lock or abutment to prevent the ram 38 from movingto the left, as viewed in FIG. 4. However, the rod members 53 may bedisplaced from the groove, as will be- 3 hereinafter explained, topermit the ram 38 to move to the left, as illustrated in FIG. 7.

The piston 46 is provided with a threaded aperture 57 which is arrangedin registration with the stud 27 so that the stud may engage within theaperture, in the manner illustrated in FIG. 4, to retain the piston ininoperative position against movement axially of the ram.

In order to effect operation of our invention the stud 27 is caused tobe rotated approximately one-'quarter of a turn in a direction to effectdisengagement of the threaded end of the stud from the threaded aperture57 in the piston 46. In inoperative position the ram 38 is lockedagainst movement to the left, as viewed in FIG. 4, by the rod members53. Assuming that both threaded openings 19 and 21 are connected to acommon pressure line, and that the pressures on both sides of the piston46 in chamber 16 are equal, it will be seen that pressure fluid isacting on annular shoulder 40 tending to urge ram 38 to the left, asviewed in FIG. 4. After the piston I is freed for movement as in FIG. 5,the pressure of the spring 52 against the piston 46 will cause the sameto move towards the left. The rate of movement of the piston will bedetermined by the adjustment of the bleed aperture 49 which permitspressure fluid to pass from the chamber adjacent the leading face of thepiston to the chamber adjacent the trailing face of the piston. It willbe apparent that upon rotation of the threaded stem 51 an adjustment ofthe bleed aperture will be effected. The piston 46 will continue to moveto the left under the influence of the spring 52 to a point where thepiston engages the pins 56 and upon such engagement effects a rocking ofthe rod members 53 from the locking position illustrated in FIG. to theposition illustrated in FIG. 6. In this latter position the rightshoulder edge 42a of the annular groove 42 is caused to engage the flatfaces of the rod members 53 and by reason of the constant pressure onthe annular shoulder 40 the shoulder edge 42a effects a camming actionon the rod members 53 to cam the same out of the groove 42 thereby torelease the ram so that it may continue to move to the left in thedirection of the arrow indicated in FIG. 7. It will be apparent thatwhen the annular groove 42 moves to a point where it is in registrationwith the groove of O-ring 37 the chamber adjacent the leading face ofthe piston, in effect, is opened to the atmosphere so that the pressuredifferential acting on the ram 38 in a direction to move the ram to theleft is substantially increased resulting in a very rapid movement tothe ram to effect a desired rapid actuation of any device or apparatus.Also, when the ram 38 in its movement reaches a position wherein theO-ring 44 is caused to move out of the bore 24 of the end member 22, thepressure fluid within chamber 16 on the trailing side of piston 46 isdischarged as a blast through bore 24 for pressurizing or propellingpurposes.

It will be understood that if desired the ram may be completely ejectedfrom the casing or may be limited in its movement by engaging against an'abuttment or an element to be actuated.

It will be understood that the device of our invention may also beutilized in applications involving normal ambient pressures. In suchcases it is preferred that the ram 38 be biased by a spring not shownabutting the rearward or right hand end of the ram to take the place ofpressure fluid for urging the ram in a direction as indicated by thearrow in FIG. 7. As in the first described embodiment, the piston 46will move axially of the ram, from the right to the left, under theinfluence of the spring 52 and the rate of movement will be controlledby the adjustment of the bleed aperture 49. Of course, under the lastmentioned conditions of operation, no pressurized fluid is available inthe chamber adjacent the trailing face of the piston for discharge as ablast or burst through the bore of the end member.

The terms air and pneumatic as used herein are intended to cover air aswell as any other gas.

Various changes coming within the spirit of our invention may suggestthemselves to those skilled in the art; hence we do not wish to belimited to the specific embodiments shown and described or usesmentioned, but intend the same to be merely exemplary, the scope of ourinvention being limited only by the appended claims.

We claim:

1. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and provided with end walls,each having a central bore,

(b) a piston having a central bore and being moveable within saidchamber, all of said bores being disposed in axial registration, 7

(c) a ram slideably mounted in all of said bores,

((1) means biasing said piston in one direction,

(e) means in said piston for bleeding air from the chamber portionadjacent the leading face of the piston to the chamber portion adjacentthe trailing face of the piston to control the rate of travel of saidpiston,

(f) said ram having an annular groove,

(g) releasable latching means within said chamber effective to lock saidram against movement,

(h) said latching means including a pair of oppositely disposed rodmembers arranged to be received in said annular groove and to extendtransversely of said ram to lock said ram against movement, and

(i) resilient means biasing said rod members into said groove,

' (j) each of said rod members having a flat camming surface and aprojection extending in angular relation to the plane of said surfaceand to the axis of said ram,

(k) said projections being arranged to be engaged by said piston wherebysaid rod members are cammed out of said groove to release said ram formovement.

2. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and provided with end Walls eachhaving a central bore,

(b) a piston having a central bore and being moveable within saidchamber, all of said bores being disposed in axial registration,

(c) said body having inlet ports arranged to admit pressure fluid intosaid chamber on opposite faces of said piston,

(d) a ram having a first cylindrical portion and a second cylindricalportion, the latter being smaller in diameter than the former,

(e) said first cylindrical portion being slideably received in the boreof the piston and in the bore of one end wall,

(f) said second cylindrical portion being slideably received in the boreof the other end wall,

(g) the differential area at the juncture of said first and secondcylindrical portions of said ram affording an annular surface on whichpressure fluid may act to bias the ram in one direction,

(h) spring means circumposed about said ram and biasing said piston inone direction,

(i) means in said piston for bleeding pressure fluid from the chamberportion adjacent the leading face of the piston to the chamber portionadjacent the trailing face of the piston to control the rate of travelof said piston, and

(j) releasable latching means within said chamber effective to lock saidram against movement,

(k) said piston being arranged to move into engage- ,(c) said bodyhaving inlet ports arranged to admit pressure fluid into said chamber onopposite faces of said piston,

4 (d) a ram having a first cylindrical portion and a second cylindricalportion, the latter being smaller in diameter than the former,

(c) said first cylindrical portion being slideably receivedin the boreof the piston and in the bore of one end wall,

(f) said second cylindrical portion being slideably received in the boreof the other end wall,

(g) the differential area at the juncture of said first and secondcylindrical portions of said ram affording an annular surface on whichpressure fluid may act to bias the ram in one direction,

(h) spring means circumposed about said ram and biasing said piston inone direction,

(i) means in said piston for bleeding pressure fluid from the chamberportion adjacent the leading face of the piston to the chamber portionadjacent the trailing face of the piston to control the rate of travelof said piston, and

(j) said ram having an annular groove in said first cylindrical portion,

(k) releasable latching means within said chamber effective to lock saidram against movement,

(1) said latching means including a pair of oppositely disposed rodmembers arranged tobe received in said annular groove and to extendtransversely of said ram to lock said ram against movement, and

(m) resilient means biasing said rod members into said groove,

(11) each of said rod members having a flat camming surface and aprojection extending in angular relation to the plane of said surfaceand to the axis of said ram,

() said projections being arranged to be engaged by said piston wherebysaid rod members are cammed out of said groove to release said ram formovement under the influence of pressure fluid.

4. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and providedv with end wallseach having a central bore,

(b) a piston having a central bore and being moveable within saidchamber, all of said bores being disposed in axial registration,

(0) said body having inlet ports arranged to admit pressure fluid intosaid chamber on opposite faces of said piston,

(d) a ram having a first cylindrical portion and a second cylindricalportion, the latter being smaller in diameter than the former,

(e) said first cylindrical portion being slideably received in the boreof the piston and in the bore of one end wall,

(f) said second cylindrical portion being slideably received in the boreof the other end wall,

(g) the differential area at the juncture of said first and secondcylindrical portions of said ram affording an annular surface on whichpressure fluid may act to bias the ram in one direction, t

(h) spring means circumposed about said ram and biasing said piston inone direction,

(i) means in said piston for bleeding pressure fluid from the chamberportion adjacent the leading face of the piston to the chamber portionadjacent the trailing face of the piston to control the rate of travelof said piston, and

(j) said ram having a pair of diametrically opposed groove portions,

(k) abutment means arranged to be received in said groove portions andto lock said ram against axial movement in said one direction, and

(1) means associated with said abutment means and arranged to be engagedby said piston whereby said abutment means is'cammed' out of said grooveand said ram is released for axial movement.

5. In combination,

(-21) a ram supported in bearings for axial sliding movement and havingoppositely disposed groove portions,

(b) a member slideably supported on said ram,

-(c) means biasing said member in one direction,

(d) means controlling the rate of movement of said member relative tosaid ram,

(e) releasable latching means effective to lock said ram againstmovement,

(-f) said latching means including a pair of oppositely disposed rodmembers arranged to be received in said groove portions and to extendtransversely of said ram to lock said ram against movement, and

(g) resilient means biasing said elements into said groove portions,

(h) each of said rod members having a flat camming surface and aprojection extending in angular relation to the plane of said surfaceand to the axis of said ram,

(i) said projections being arranged to be engaged by said piston wherebysaid rod members are cammed out of said groove portions to release saidram for movement. 6. The invention as defined in claim 1 in which theram is pressure biased in the same direction as the piston.

7. The invention as defined in claim 5 in which the ram is pressurebiased in the same direction as the piston.

8. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and provided with end walls eachhaving a central bore,

(b) 'a piston having a central bore and being movable Within saidchamber, all of said bores being disposed in axial registration,

(c) said body having inlet ports arranged to admit pressure fluid intosaid chamber on opposite faces of said piston,

(d) a ram having a first cylindrical portion and a second cylindricalportion, the latter being smaller in diameter than the former,

(c) said first cylindrical portion being slideably received in the boreof the piston and in the bore of one end wall,

(f) said second cylindrical portion being slideably received in the boreof the other end wall,

(g) the differential area at the juncture of said first and secondcylindrical portions of said ram affording an annular surface on whichpressure fluid may act to bias the ram in one direction,

(h) spring means circumposed about said ram and biasing said piston inone direction,

(i) means in said piston for bleeding pressure fluid from the chamberportion adjacent the leading face of the piston to the chamber portionadjacent the trailing face of the piston to control the rate of travelof said piston, and

' (j) releasable latching means within said chamber effcctive to locksaid ram against movement,

(k) said piston being arranged to move into engagement with saidlatching means thereby to release said r-am for movement under theinfluence of pressure fluid,

(l) the movement of said ram opening a passage in the bore of the otherend wall to permit discharge through said passage of pressure fluid fromthe chamber portion adjacent the trailing face of the piston.

9. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and provided with end walls eachhaving a central bore,

(b) a piston having a central bore and being movable within saidchamber, all of said bores being disposed in axial registration,

() said body having inlet ports arranged to admitv pressure fluid intosaid chamber on opposite faces of said piston,

(d) a ram having a first cylindrical portion and a second cylindricalportion, the latter being smaller in diameter than the former,

(6) said first cylindrical portion being slideably received in the boreof the piston and in the bore of one end wall,

(f) said second cylindrical portion being slideably received in the boreof the other end wall,

(g) the differential area at the juncture of said first and secondcylindrical portions of said ram affording an annular surface on whichpressure fluid may act to bias the ram in one direction,

(h) spring means circumposed about said ram and biasing said piston inone direction,

(i) means in said piston for bleeding pressure fluid from the chamberportion adjacent the leading face of the piston to the chamber portionadjacent the trailing face of the piston to control the rate of travel:of said piston, and

(j) said ram having an annular groove in said first cylindrical portion,

(k) releasable latching means within said chamber effective to lock saidram against movement,

(I) said latching means including a pair of oppositely disposed rodmembers arranged to be received in said annular groove and to extendtransversely of said ram to lock said ram against movement, and

(m) resilient means biasing said rod members into said groove,

(11) each of said rod members having a flat camming surface and aprojection extending in angular relation to the plane of said surfaceand to the axis of said ram,

(0) said projections being arranged to be engaged by said piston wherebysaid rod members are cammed out of said groove to release said rain formovement under the influence of pressure fluid,

(p) the movement of said ram opening a passage in the bore of the otherend wall to permit discharge through said passage of pressure fluid fromthe chamber portion adjacent the trailing face of the piston.

10. The invention as defined in claim 3 in Which re leasable means areprovided for securing the piston against movement.

References Cited by the Examiner UNITED STATES PATENTS 2,677,417 5/1954Logan et a1 92l30 2,693,852 11/1954 Corbett 251-49 3,020,094 2/1962Murty et al 188170 3,188,922 6/1965 Cruse 9263 EDGAR W. GEOGHEGAN,Primary Examiner.

SAMUEL LEVINE, Examiner.

I. C. COHEN, Assistant Examiner.

1. A PNEUMATIC TIMING DEVICE COMPRISING, (A) A BODY HAVING A CYLINDRICALCHAMBER AND PROVIDED WITH END WALL, EACH HAVING A CENTRAL BORE, (B) APISTON HAVING A CENTRAL BORE AND BEING MOVEABLE WITHIN SAID CHAMBER, ALLOF SAID BORES BEING DISPOSED IN AXIAL REGISTRATION, (C) A RAM SLIDEABLYMOUNTED IN ALL OF SAID BORES, (D) MEANS BIASING SAID PISTON IN ONEDIRECTION, (E) MEANS IN SAID PISTON FOR BLEEDING AIR FROM THE CHAMBERPORTION ADJACENT THE LEADING FACE OF THE PISTON TO THE CHAMBER PORTIONADJACENT THE TRAILING FACE OF THE PISTON TO CONTROL THE RATE OF TRAVELOF SAID PISTON, (F) SAID RAM HAVING AN ANNULAR GROOVE, (G) RELEASABLELATCHING MEANS WITHIN SAID CHAMBER EFFECTIVE TO LOCK SAID RAM AGAINSTMOVEMENT, (H) SAID LATCHING MEANS INCLUDING A PAIR OF OPPOSITELYDISPOSED ROD MEMBERS ARRANGED TO BE RECEIVED IN